Heretofore, the typist when desiring to center a heading or title, had several alternative techniques at her disposal. The first is one where the typewriter is positioned such that the printing point is at the left margin. Upon this positioning of the typewriter, if the typewriter had a no print feature the no print control is activated and the heading or title to be centered was then keyed. This caused the typewriter to escape in its normal mode and at the same time prevented marks from being placed upon the copy sheet. At the completion of the keying, the typist then determined the distance that the print point had traversed from the left margin in character spaces and divided by two. This number was then substracted from the relative position number designating the center of the page or the center point around which the heading was to be positioned. This gave a relative position to which the print point of the typewriter was manually adjusted. The typewriter was then enabled for printing and the entry typed in a normal manner.
A second technique was to place the print point of the typewriter at the center line point and then mentally group letters in the heading which is to be typed in pairs. As each pair was grouped and thought of, the backspace control for the typewriter was depressed once.
Upon the completion of the mental grouping of all characters into pairs and the appropriate number of depressions of the backspace mechanism, the print point was properly positioned for typing. This technique is most predominantly used on those typewriters without a no print capability.
A third approach was to count the letters and spaces in the heading or entry, divide by two, and substract the result from the center point position, yielding a relative position for the beginning of the title or entry.
As can be seen from the foregoing, all required concentration on the part of the typist.
Also, all required some type of manipulation which was relatively abnormal with respect to the normal typing function.